JWT Decoder
Decode JWT tokens instantly to view Header and Payload info. Converts expiration and issuance timestamps to readable dates.
Token Integrity Check
Syntactically valid JWT structure detected. Payload extracted successfully.
JWT Decoder Use Cases
Frequently Asked Questions
Q. Is my token data sent to a server?
No, decoding happens entirely in your browser. Your sensitive token data never leaves your device.
Q. Can this tool verify the JWT signature?
Yes, if you provide the Secret or Public Key, it can verify the integrity of the signature.
Q. What is the difference between JWS and JWE?
JWS (Signed) provides integrity and authenticity, while JWE (Encrypted) provides data confidentiality.
Q. How do I check if a token is expired?
The decoder automatically highlights the "exp" claim and compares it with the current time.
Q. Does it support custom claims?
Yes, it decodes all standard and custom JSON claims found in the token payload.
JWT Architecture
| Part | Component | Description |
|---|---|---|
| Header | Algorithm & Type | Defines the signing algorithm (e.g., HS256) and token type. |
| Payload | Claims | Contains the user data and claims (e.g., sub, iat, exp). |
| Signature | Integrity | Ensures the token hasn't been tampered with using a secret key. |
Security Best Practices
Follow these guidelines to maintain secure token handling.
Never store sensitive secrets (passwords) in the payload.
Always transmit tokens over secure HTTPS connections.
Use short expiration times to minimize the impact of token theft.
⚠️ Warning: JWT is NOT encryption. Anyone with the token can see the payload data.
Key Features
- Instant real-time JWT decoding and syntax highlighting
- Automatic conversion of Unix timestamps to human-readable dates
- Clear visual separation of Header, Payload, and Signature
- Full support for Base64URL and various signing algorithms
Professional online JWT decoder and debugger. Inspect header, payload, and signature of JSON Web Tokens instantly with security best practices.